Sheffield United may have the goalkeeper of Christmas future, but it was the goalkeeper of Christmas past who stopped them rounding off a fantastic year at Bramall Lane with three points.
Foster's eight-cap England career may be behind him but he remains one of the Premier League's top goalkeepers.
He made Gerard Deulofeu's opening goal, but his most important contribution was deny John Fleck the winner for a below-par Sheffield United, who were still the better side of a lukewarm Boxing Day encounter.
The Blades were far from their best but pushed hard for victory in the second half. Manager Chris Wilder running down the touchline to retrieve the ball in stoppage time showed how much he wanted the win.
But Foster ensured they had to make do with a 1-1 draw at home to bottom-of-the-table Watford. It could have been even worse, with Deulofeu only fractionally off target with a late free-kick he was lucky to get.
When it kicked off ten minutes late because of problems with fans getting into the ground, the first half was not really worth the wait, even if both sides found the net.
Throughout the game the long ball was the biggest threat, and in the first half it was Watford who were armed with it. Twice in the early stages, Chris Basham had to sweep up to avert danger.
Oli McBurnie, who retained his place in a side whose only change was the return of John Fleck from suspension, led the way for the Blades at that stage, but was frustrated by Foster.
The goalkeeper showed his reflexes were still sharp in the 11th minute, getting down low and quickly when McBurnie steered a driven Jack O'Connell cross goalwards. His near-post save from McBurnie's header a minute later was less spectacular, but still needed.
Despite that pressure, it was the Hornets who took the lead, in the 27th minute. Foster's routine long ball was flicked on and Deulofeu outsprinted the Sheffield United defence, took his time and picked his spot past Dean Henderson. It was a poor goal to concede.
It took ten minutes for the Blades to equalise, George Baldock brought down as he ran onto a John Lundstram lay-off. The wing-back was in the penalty area but heading out of it when Will Hughes unnecessarily clipped him. Foster guessed the right way but the power of Oliver Norwood's penalty meant he still could not stop it.
The Blades restarted with more intensity, Baldock winning a free-kick after 20 seconds, but it was more perspiration than inspiration.
Lys Mousset came off the bench in the 63rd minute and played a similar role to Deulofeu. He almost conjured a winner within seconds, speeding off down the line after an exchange of passes with David McGoldrick, then crossing for Fleck. The midfielder must have thought he had scored but, with his weight moving the wrong way, Foster not only managed to get to the ball, but scoop it over the post.
The Blades continued to push forward, but Foster's near-post save from Enda Stevens, over in the inside-right channel, underlined it was not going to be their day. John Egan's header from the corner was blocked too.
At least they did not suffer one last sucker punch.
Deulofeu had ended the first half with a dipping free-kick that did not dip enough after Norwood's foul on him gave the Spaniard a sight of goal, and was lucky to get another chance in the 82nd minute, when Jack O'Connell appeared to win the ball cleanly, but was penalised.
With Henderson rooted, Deulofeu put his free-kick just wide.
Sheffield United: Henderson; Basham, Egan, O'Connell; Baldock, Lundstram, Norwood, Fleck, Stevens; McGoldrick, McBurnine (Mousset 63).
Unused substitutes: L Freeman, Sharp, Robinson, Jagielka, Verrips, Besic.
Watford: Foster; Mariappa, Kabasele, Cathcart, Femenia; Capoue, Chalobah (Dawson 88); Sarr (Pereyra 46), Hughes, Deulofeu; Deeney (Gray 80).
Unused substitutes: Gomes,Quina, Success, Dele-Bashiru.
Referee: D Coote (Nottinghamshire).